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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/54348] confusing error reported for type mismatch in conditional expression : "error: no match for ternary 'operator?:' in 'false ?"
Date: Tue, 21 Aug 2012 19:52:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54348

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-08-21 19:51:53 UTC ---
(In reply to comment #0)
> Shouldn't g++ be complaining about initializing a string with a list<string>
> rather than this cryptic "no match for ternary 'operator?:'" here ?

No, not really.

The object being initialized by the result of the condition expression is
irrelevant, the conditional expression isn't valid whether or not you're using
it to initialize another object.

In this reduced version it wouldn't make sense to refer to initializing any
object with any other:

struct A {} a;
struct B {} b;

void f()
{
    false ? a : b;
}